It has long been considered desirable for governmental and commercial purposes to have a high altitude "platform" from which a payload (e.g. radiation sensors or other devices) can operate.
It has previously been proposed to power aircraft by solar cells, and U.S. Pat. No. 4,415,133 is directed to such an aircraft. Other solar cell powered aircraft have also been proposed. However, although the energy provided by solar cells is adequate to power lightweight aircraft while they are in the sunlight, it is inadequate to provide sufficient power to store in batteries, rechargeable fuel cells, or the like, so that a solarpowered aircraft can remain in the air day and night for prolonged periods of time.
Another proposal for a high altitude platform involved the U.S. Navy HI-SPOT blimp or balloon project. Apparently, some consideration was given to the possibility of using Long Wave Infrared Radiation (LWIR) from the earth to provide continuous power to such a blimp or balloon. An article discussing this possibility is entitled "A Radiation Thermoelectric Power Converter", L. W. Lemley, Naval Research Laboratory, pages 20 through 26, Symposium Report. It is understood that the possibility of using LWIR to power the blimp or balloon continuously, has not been implemented.
Accordingly, a principal object of the present invention is to provide an aircraft which is capable of staying aloft at high altitudes day and night for many months, or even years.
Another problem is the launching of a low power, high altitude, lightweight structure, aircraft and implementing ascent to the desired altitudes of 60,000 to 110,000 feet.
Another object of the present invention is to launch such an aircraft, and to accomplish the launch in secrecy.